Duv definition
Duv means delta (u, 2/3v'), which is a metric that
Duv means the closest distance from the chromaticity coordinate of the light source to the Planckian locus on the International Commission on Illumination (CIE) (uʹ, 2/3 vʹ) coordinates with ʺ+ʺ sign for above and ʺ‐ʺ sign for below the Planckian locus.
Duv means delta (u, 2/3v'), which is a metric that describes the distance of a light color point from the planckian locus.